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Question 1.139: Reconsider Problem 1–138. Using EES (or other) software, plo...

Reconsider Problem 1–138. Using EES (or other) software, plot the rate of heat loss through the window as a function of the U-factor. Discuss the results.

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“GIVEN”

A=1.2*1.8 “[m^2]”

T_1=20 “[C]”

T_2=-8 “[C]”

“U=1.25 [W/m^2-C], parameter to be varied”

“ANALYSIS”

Q_dot_window=U*A*(T_1-T_2)

 

 

U \left [ W/m^{2} \cdot C \right ] Q_{window} \left [ W \right ]
1.25 75.6
1.75 105.8
2.25 136.1
2.75 166.3
3.25 196.6
3.75 226.8
4.25 257
4.75 287.3
5.25 317.5
5.75 347.8
6.25 378
118

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